2) Former President Park's government agreed to American requests to deploy the US Army's THAADmissile system in the center of South Korea (Terminal High Altitude Area Defense anti-ballistic missile system, in Seongju County, North Gyeongsang Province). Highly alarmed by what they see as an arms escalation, China instituted very-costly commercial boycotts of South Korea. THAAD could easily further trigger regional chaos, but there's also still a few weeks before it goes live & operational (reportedly June 2017). Does that create a dangerous window?

3) US President Trump is discovering overseas military action diverts American attention from domestic corruption, official incompetence, and other internal weaknesses. But Syrian intervention is unsustainable, as Americans resist investing more in the morass of the Middle East. North Korea (DPRK) is a convenient enemy. The seemingly achievable goal of regime change may entail substantial regional costs, but perhaps Trump & Co. will take the risk.

Hint: Recent news that Steve Bannon is no longer a regular member of the National Security Council ... better positions the White House Chief Strategist away from nuclear blowback & fallout.